字符串应用---kmp算法

代码：

#include <iostream>
#include<string>

using namespace std;
const int MAXM=100;

int nextTable[MAXM];


//得到naxtTable表的值
void GetNextTable(string pattern){
int m=pattern.size();
int j=0;
nextTable[j]=-1;
int t=nextTable[j];
while(j<m){
    if(t==-1||pattern[t]==pattern[j]){
        t++;
        j++;
        nextTable[j]=t;
    }
    else{
        t=nextTable[t];
    }
}

}




//定义kmp算法
int kmp(string text,string pattern){
GetNextTable(pattern);
int n=text.size();
int m=pattern.size();
int i=0;
int j=0;
while(i<n&&j<m){
    if(j==-1||text[i]==pattern[j]){
        i++;
        j++;
    }
    else{
        j=nextTable[j];
    }

}
if(j==m){
    return i-j;
}
return -1;
}


int main()
{string text,pattern;
getline(cin,text);
getline(cin,pattern);

int position=kmp(text,pattern);
cout<<position<<endl;

    return 0;
}